An activist who co-founded the Working Families Party is snubbing Democratic Gov. Andrew Cuomo and backing Cuomo’s most high-profile primary challenger, Cynthia Nixon.

Bertha Lewis, the head of the Black Institute who formerly ran the left-wing firebrand group ACORN, said she first met “Sex and the City’’ actress Nixon at a rally to protest school-funding cuts in 2002. They both were arrested for blocking the entrance to City Hall.

She said Nixon’s activism impressed her, and recalled that when Nixon called to ask whether she should run, Lewis said, “Run, baby, run!”

Cuomo has moved to the left during his second term, after Zephyr Teachout pulled a third of the vote against the governor in the Democratic primary in 2014. Lewis backed Teachout then.

Cuomo has since banned fracking and passed laws boosting the minimum wage, requiring employers to provide workers paid family leave, and enacting a free tuition program at public colleges.
But Lewis said Cuomo is not an acceptable progressive in her eyes.

“No, no, definitely not. He talks a good game,” she said.

Lewis cited Cuomo’s “disingenuous” recent visits to NYCHA complexes in year eight of his governorship and discovering there are slum-like conditions.

“Really?” she said. “This guy used to be federal HUD secretary. Come on!”